how improve Fps?

[GetOutOfBox]

A new video card is probably a good idea (I suggest a Radeon 6870, great performance for the money, you can get one for around $199). Your Radeon 4870 should easily be able to handle vanilla Oblivion, but a heavily modded Oblivion is an entirely different beast. Adding a mod like Qarls Texture Pack adds a bunch of potential bottlenecks, your harddrive may not be fast enough to serve up the larger texture files to your video card, or your video cards memory may be to slow, your motherboards QPI/HyperTransport to slow, etc, etc.

 

I suggest purchasing an SSD to put your performance intensive games on, that will allow for much quicker loads, and less stuttering. A new video card will reduce the performance penalty of shader intensive mods like OBGE and allow for less stuttering as larger textures are loaded into memory.